|Livestock Research for Rural Development 8 (1) 1996||
Citation of this paper
Smallholder milk production, milk handling and utilization: A case study from the Nharira/Lancashire farming area, Zimbabwe
A N Mutukumira(1), D M J Dube, E G Mupunga(2) and S B Feresu(3)
(1) Dept of Food Science, Agricultural University of Norway, P O Box
5036, N-1432 Aas, Norway.
(2) Zimbabwe Oil Press Project, P O Box 1390, Harare, Zimbabwe.
(3) Dept of Biological Sciences, University of Zimbabwe, P O Box MP167, Mount Pleasant, Harare, Zimbabwe
Dairy Development Programme, Agricultural & Rural Development Authority,
PO Box CY1420, Causeway, Harare, Zimbabwe.
This paper presents data collected from the Nharira/Lancashire Farming Area which runs a smallholder dairy scheme in Zimbabwe. Historically, the smallholder sector has been fairly insignificant in milk production as milk was mainly supplied to the dairy industry by large-scale commercial producers. Since 1983, it has been part of government policy, however, to encourage farmers in the smallholder sub-sector to produce milk on a commercial scale as a source of the much needed income. Membership of the smallholder dairy sector is estimated at 2000, of which about 800 produce and sell milk. This study examined milk production and utilization in the Nharira/Lancashire Region during the period January to December 1993. The main breeds kept by milk producers in this area were exotic dairy breeds, indigenous Mashona breed (Bos indicus) and cross-bred animals. Exotic dairy cows produced more milk than the other two groups. Milking was done by hand and most of the producers used bicycles to transport milk to the collection centre. The milk was sold fresh or after it was fermented to naturally fermented or cultured milk. Raw market milk was mostly consumed in tea, while the two fermented milks were mainly eaten with sadza, a local food, and with other cereal-based food products.
Keywords: milk production, smallholder dairying, milk handling and utilization.
In Zimbabwe, milk production has mainly developed among large scale commercial producers. According to an estimation by the National Association of Dairy Farmers (unpublished work) they are about 450 commercial farmers who keep most of the dairy herds and supply nearly all the national milk intake. These farmers compare favourably with those found in Europe, North America, New Zealand and Australia. The predominant dairy breed is the black and white Holstein-Friesian, although a number of other breeds such as the Jersey, Ayrshire, Guernsey and the Red Dane are also represented, but in smaller numbers (Smit 1989; Ball et al 1990; Henson 1992).
In addition to these large-scale milk producers, there are ten smallholder dairy schemes set up through the Dairy Development Programme (DDP) based on communal, small scale or resettlement farmers [Communal farmers: Individual families cultivate their own susbsistence plots and they have no title to own the land (Ball et al 1990); Small-scale farmers: farmers have the title to own land (Ball et al 1990); Resettlement farmers: Farmers are allocated land on former large-scale commercial farms, and they have no title to the land (Ball et al 1990)] (Borland 1990; Pascoe and Borland 1990; Henson 1992; Mupunga and Dube 1993). Traditionally, these farmers keep cattle as a source of draught power, manure, wealth and status (Ball et al 1990), but with suitable infrastructure and better management, this sector has the potential of producing about 250 million litres of milk per year (Borland 1990). At present there are only few studies available which specifically treat smallholder dairying in Zimbabwe and even fewer which focus on milk handling and utilization at the milk collection centres set up for this sector. Against this background, a study of dairy production was undertaken in the Nharira/Lancashire smallholder farming area. The primary objective of the survey was to give an overview of the status of milk production in the area, as part of a broad-based research programme with a view to improving the planning and development of rural dairy processing. Thus, the objectives of the study were to investigate (i) the delivery of milk to the Nharira/Lancashire Milk Collection Centre in 1993; (ii) the handling and utilization of milk at the collection centre and in the producing area during the same period.
The development of smallholder dairying
Following Zimbabwe's independence in 1980, there was a notable increase in disposable income combined with relatively low consumer prices, which resulted in a high demand for food commodities, including dairy products. Furthermore, prices of dairy products were kept low by government subsidies (McCabe and McCullum 1984; Pascoe and Borland 1990). In 1984, urban milk consumption was approximately 68 litres per capita compared to 19 litres per capita in rural areas. According to Henson (1992) per capita rural consumption estimates reflect supply rather than demand; a suppressed rural demand of 45 litres per capita was estimated (Henson 1992). The concept of smallholder dairying was therefore adopted as a possible means of increasing milk production to meet this demand and to improve milk supply, especially to the rural population situated far from the formal distribution centres (Karunaratne and Wagstaff 1985). A dairy development programme was established in 1983, whose mandate was to set up smallholder dairy schemes with participation from communal, small-scale and resettlement farmers.
At present, there are ten smallholder dairy schemes at various stages of development operating in five provinces. Each scheme has a milk collection centre equipped with collection and storage facilities. Four schemes are part of the national bulk milk collection scheme and therefore collected milk is delivered to processors located in major towns. Milk collected at the remaining six schemes is sold fresh or processed into fermented milk. The latter schemes were dependent on near-by local markets (Henson 1992; Mupunga and Dube 1993). In addition, the dairy programme provides facilities which include assistance to members with acquisition of cattle, access to agricultural inputs and advice on animal management (Dairy Development Programme, personal communication). In this way, the programme is designed to broaden the production base of milk and to increase the amount (and number) of available dairy products to rural consumers thus making a significant contribution to rural development. If successful, smallholder dairying could provide regular income and all year round employment for rural people, and might counteract rural migration and reduce growth of urban slums (Bachmann 1979, 1985a,b; Kuranaratne and Wagstaff 1985; Walshe et al 1992). It could also be a means of intensifying land use where land is a limiting resource.
In recent years, membership of the smallholder dairy sector has increased to approximately 2000, of which about 800 members produce and sell milk at present. The programme has also initiated the formation of producer associations responsible for running the affairs of members (Pascoe and Borland 1990; Henson 1992; Mupunga and Dube 1993).
Similar schemes have been successful in other African countries such as Kenya where small-scale holders of the coastal region have for many years supplied Mombasa with milk. In Malawi the marketing of milk from traditional herds close to centres of consumption has been accepted as part of development strategies for that country (Bessell and Daplyn 1977; Agyemang and Nkhonjera 1986; Walshe 1990).
General characteristics of the country
Zimbabwe is situated within the tropics (between latitudes 15ºS, 22ºS and longitudes 26ºE, 34ºE) in sub-Sahara Africa and covers approximately 390 000 km2. It, however, consists mainly of a plateau and as a result the climate is predominantly subtropical, being cooler and drier than most areas within the tropics (Thompson and Purves 1978; Steinfeld 1988; Ball et al 1990). Three distinctive seasonal variations prevail in all areas, comprising a dry winter, a hot dry spring and a rainy season. About a third of the country receives more than the 700 mm of rain per annum which is required for semi-intensive farming, and only the central plateau and other regions at altitudes above 1 000 metres are suitable for dairy production (Steinfeld 1988; Pascoe and Borland 1990). The entire country is susceptible to drought periods because the main rains are related to air masses of the inter-tropical convergence zone (Ngara et al 1983). This creates conditions which make rainfed cropping difficult for most of the country and grazing has to be supplemented either by provision of fodder through irrigation or by irrigated pastures (Pascoe and Borland 1990; Smith 1989; Henson 1992). Therefore fodder conservation constitutes an important part of dairy farming activities.
Nharira/Lancashire farming area is located 170 km south of Harare, within longitudes 31ºE, 31º15'E and latitudes 19º S, 19º15' S, at 1458 metres above sea level. It has an estimated population of 8,000 distributed among ca 1,700 households, with an average household size of 5 (CSO 1992). Its annual rainfall ranges from 650 to 800 mm and has a unimodal pattern with high levels falling from November to April and with only small amounts received in June and July (Figure 1). The rainy season is characterised by infrequent heavy falls and fairly dry mid-season spells. The effectiveness of rainfall is further reduced by high temperatures (McCabe and McCullum 1984; Steinfeld 1988). The rainfall pattern of the area for the periods 1992/93 and 1993/94 is shown in Figure 1. The 1992/93 period received more rain, about 950 mm, than the 1993/94 period with approximately 680 mm, which is a marginal amount expected of the region.
Average maximum and minimum temperatures for the project area are shown in Figure 2. Maximum and minimum temperatures for the two periods are similar. The lowest temperatures were recorded in June and July. Figure 2 shows that the highest temperatures were recorded in September and October. As noted previously, these are generally lower than temperatures expected of a tropical region, partly because of the altitude of the area. This can indeed be advantageous for better keeping quality of milk.
The soil in the area is of granite origin and is classified as weakly to strongly sodic (Thompson and Purves 1978; Bennett 1985). The vegetation is mainly of bare ground with some scattered trees and tufts of grass. Farming is semi-intensive and suitable farming systems are livestock production complemented by fodder crop production. Cash cropping is possible under good management and on soils of high moisture availability (Steinfeld1988).
Justification for selection of the project area
The selection of the study area was based mainly on the following factors. Firstly, the Nharira/Lancashire dairy scheme was not part of the bulk milk collection scheme, and therefore all milk intake was marketed locally (Henson, 1992; Mupunga and Dube, 1993), making it ideal to study some aspects of milk handling, utilization and marketing. Surveys carried out by the national milk body indicated an increased potential of milk production in the smallholder farming region, particularly during the rainy season, mainly due to availability of adequate feeds and improved animal management (DMB 1988).
Consumers in this area have a tradition of consuming naturally soured milk called amasi (Mutukumira 1995). This factor was particularly important in view of the need to upgrade the production of preferred cultured milks for the local market. Further, the development of better ways of producing amasi would be, in our opinion, a way of preserving traditional foods and cultural heritage.
The Nharira/Lancashire milk collection centre was the only smallholder facility producing and marketing fermented milks when the study was initiated. This activity coincided with our primary objective of extending the knowledge of traditionally fermented milks in the country and developing suitable dairy starter cultures for local use. The ultimate goal of the research is to develop means of processing milk in simple, small plants into marketable products with good keeping quality, using simple, locally produced machines. Such developments should create employment opportunities, improve agricultural productivity and generally contribute towards the industrialization of rural areas where about two-thirds of the Zimbabwean population lives (Karunaratne and Wagstaff 1985; Borland 1990).
Survey Methodology and Data Collection
At the inception of this study, the Nharira/Lancashire Farming Area dairy scheme had 192 registered members, of which 34 were active milk producers [Active smallholder milk producer: A farmer who produced and delivered milk to the milk collection centre during the survey]. The active milk producers constituted the population size of the study and comprised 18 small-scale and 16 communal farmers. A list of the producers was obtained from the Nharira/Lancashire dairy project office, and the use of this list meant that farmers who marketed their produce outside the scheme or who were not registered with the scheme were not included in the survey. Although this may appear to have a slight bias in the selection of participants, the assumption was that most farmers in the area had joined the programme in view of the attractive facilities it offered. The study was preceded by the severe drought of 1991/1992 which affected most of sub-Saharan Africa. Consequently, this had adverse effects on dairy farming and had reduced the number of active smallholder milk producers (DDP personal communication).
Formal and informal data were collected over 12 months of 1993 by personal interviews and by the use of structured questionnaires issued to these smallholder milk producers. Two persons who were familiar with local farming activities and location of the farms assisted with the collection of data. The respondent was the person most directly involved with milk production. The design of the questionnaire was based on similar studies by Bessell and Daplyn (1977), Launonen et al (1985) and Agyemang and Nkhonjera (1986). The questionnaire was designed with the knowledge that registered active members kept records of their activities and consideration was given to questions which relied on memory recall for some of the responses. The questionnaire included questions on milk production, handling and processing.
Results and discussion
The smallholder dairy herd was composed of 152 cows and 66 heifers. The main breeds of dairy cattle found in the area were exotic dairy breeds (Red Dane, Jersey, Friesian) crossbreds and indigenous (Table 1). The predominant breed was the Red Dane, followed by the indigenous Mashona breed (Bos indicus). The number of Red Dane cows was high partly because they were initially given to smallholder farmers by Heifer Project International as support to develop smallholder dairying in the project area. High numbers of the indigenous breed were not unexpected as a majority of the communal farmers in Zimbabwe traditionally keep this breed (Ball et al 1990; Pascoe and Borland 1990; Mupunga and Dube 1993).
|Table 1: Main dairy breeds found in Nharira/Lancashire Farming Area and typical milk yields.|
*Average milk yield above calf off-take. ** At peak of lactation
Average lactation periods and milk yields for the respective breeds are shown in Table 1. Indigenous cows produced approximately a quarter of the mean lactation yield obtained from exotic cows. This could be a reflection of their poor genetic potential for milk production (Perry et al 1987; Leaver 1987; Preston 1989) and/or the level of animal management of this particular breed in the smallholder sector. Milk yields from indigenous cows have been reported to be influenced by the milking system used. Work done by Khombe and Dube (1987) showed that calf stimulus increased milk let-down in Mashona cows. The lack of calf stimulus might have further contributed to the lower milk yields from the indigenous cows. Similar milk yield levels from breeds shown in Table 1 have been reported by other investigators (Steinfeld 1988; McCabe and McCullum 1984; Smith 1989; Henson 1992; Mupunga and Dube 1993).
Management of smallholder dairy farms
Most work on the majority of farms was done by the family, making labour problems very minimal. With larger herds, however, a greater proportion of the work was carried out by employed staff and in such cases labour management increased in importance. There was disparity in the size of available land between the small-scale commercial farmers (SSCF) and communal farmers (CF) within the smallholder farming sector. The average sizes of arable land were 16 and 3 acres repectively. The SSCF farmers had established paddocks and cultivated grasses such as Napier, Rhodes, Bana, Star and leguminous plants for fodder. Cattle were partially zero-grazed and the animals were fed with hay as supplementary feed during the dry season. Liberal amounts of a mixture of maize bran and concentrates were also used as supplements. The dairy programme encouraged farmers (SSCF and CF) to use silage as supplement feed during the dry season. Cattle from the CF mainly depended on pasture grazing due to smaller sizes of arable land and lack of adequate financial resources. SSCF dairy cows were confined in fenced paddocks for easy detection of oestrus and to avoid contact with indigenous bulls. The average age at first calving was 30 months and the calving interval was 420 days. The relatively long calving interval although quite acceptable, might be indicative of poor heat detection skills and/or poor nutrition status, especially for cows which freshen during the dry period (Syrstad, personal communication). The target was to reduce the calving interval to approximately 365 days by improving the breeding efficiency through the supply of bulls and better management (DDP, personal communication). Conception was generally achieved by servicing with bulls of approved breeds. Farmers from the two sub-sectors were encouraged to use purebred dairy bulls provided by DDP or approved bulls from their own stock. Artificial insemination (AI) was occasionally conducted by project staff to complement bull service. Artificial insemination is expected to increase the genetic merit of the herd through the use of semen from progeny tested bulls. Other advantages of AI are elimination of the cost of keeping bulls and reduction of the risks of acquiring venereal diseases. The main disadvantage of the AI system, however, is the need for precise detection of oestrus and the demand for skilled personnel (Leaver 1987; Preston 1989).
Following parturition, calves were separated from their dams after 4-5 days and milking was commenced thereafter. The calves were allowed to suck for short intervals of 1-2 hours twice a day after milking sessions. They were also bucket-fed with approximately 3 litres of milk and with calf-starter. The calf-starter assisted in developing their rumen for subsequent digestion of high fibre content feeds. Calves were weaned at 8 to 12 weeks depending on the physical condition of the animals.
For tick-control the cattle were either sprayed or taken to the dip-tank once a week. Six farmers used public dip-tanks, a further six used private dip-tanks and the remainder used knapsack sprayers to spray their animals. Spraying was more favoured because the method was thought to be more effective and gentle to the animals compared to the use of dip-tanks. Vaccinations against common diseases were done by the Veterinary Department and additional veterinary services were provided by staff of the DDP. De-worming was done at least twice a year, before and after the rains. Milk producers were aware of the dangers of mastitis and took adequate measures to prevent the disease. One producer indicated occurrence of mastitis in his herd. It is not clear whether this finding is a true reflection of the prevalence of mastitis in the area as the disease was not monitored during the current study. However, low prevalence of clinical and subclinical mastitis in communal farms has been reported elsewhere in Zimbabwe (Perry et al 1987). Farmers were encouraged to keep daily records of all farming activities, such as milk yields, breeding and calf births, as this information is essential for high level production efficiency (Leaver 1987).
The Dairy Regulations (1992) prescribe the type of facilities required on dairy premises and approved methods of milk handling on those farms wishing to produce milk for public consumption (Donkin 1981; Dairy Regulations 1992). As regards milk production and handling, the dairy regulations' emphasis is on `clean milk production'. Therefore the smallholder producers were required to use approved milking parlours to enhance the concept of clean milk production. The parlours were designed to facilitate correct preparation for milking and for easy cleaning of milking equipment, the walls and floors. An adequate supply of water was essential and this was obtained from deep-wells. The water was considered to be of good quality, but this aspect was not verified during this study.
Milking was done in parlours. Cows were given concentrates during milking to stimulate milk let-down. In instances where concentrates were not available, the method of allowing the calf to suck for a short period was adopted as this type of stimulation has been shown to result in high milk production (Gaya et al 1977; Alvarez et al 1980; Khombe and Dube 1987). This latter practice was more commonly used with indigenous animals. The rear legs of the cow were loosely secured together, but this was not necessary when the calf-sucking method was employed. Milking was done by hand after the udder had been rinsed with luke-warm water and then dried with disposable paper or with a towel. An approved lubricant was applied to facilitate easy milking. The lubrication also had a massaging effect which also stimulated milk let-down. Milk was collected into wide-open plastic containers or stainless steel pails, the latter were preferred by the farmers because they were easier to clean. The average milking time per cow was ten minutes. Milkers were encouraged to empty the udder to reduce the incidence of mastitis.
The milk was transferred into narrow-necked plastic containers or conventional milk churns and delivered to the centre. Producers preferred the use of milk churns as they could be cleaned more easily, but their cost was prohibitive to the majority of the farmers. In compliance with the production of clean milk, the dairy development programme was, however, assisting producers to obtain milk churns. All producers encountered difficulties when cleaning the "narrow-necked plastic containers". This might have contributed to the high microbiological counts found in the bulk milk from the collection centre (Mutukumira et al unpublished).
Delivery and utilisation of milk
|Table 2: Mode of transport used for delivery of milk and the number of producers who used that system|
|Transport system||# of producers|
|Motor vehicles (pick-up)||6|
|Delivery by walking||6|
|Situated on site||1|
Transportation of milk to the collection center was mostly by bicycle, with a few farmers using motor vehicles. Those farmers situated within close proximity of the centre delivered milk on foot (Table 2).
Total monthly milk deliveries to the centre for 1993 are shown in Figure 3 and the total amount of milk delivered for the year was about 242 000 litres. Milk production figures for the rainy season were clearly higher than those for the dry season. Lower milk deliveries during the dry season may partly be explained by the shortage of adequate cattle feed during the latter season. Similar observations have been made by other workers (Oliver 1971; Smith 1988).
Individual producer deliveries ranged from 4 to 60 litres per day with the higher figures being received from a small-scale producer and the lower figures from a communal farmer. Most producers sold nearly all the milk they obtained to the milk centre, but a few retained unspecified amounts for house-hold consumption. Milk production was seen as a source of income for meeting the family's daily requirements for other commodities and for purchasing inputs for livestock production. Some high milk producers kept pure-bred animals only for commercial milk production and obtained milk for house-hold consumption from indigenous cows. House-hold fresh milk was mainly consumed in tea or drunk fresh, and the remainder was left to sour naturally at the farm.
At the centre, three types of milk were marketed: fresh liquid, cultured and naturally fermented milk (Figure 4). Liquid milk was stored in a cooled bulk tank and sold in consumer-provided containers to reduce the cost of the product to the consumer. The two fermented milks were only produced after the demand for fresh milk had been met. Production of naturally fermented milk was achieved by souring milk in conventional milk churns at ambient temperatures for periods upto 48 hours. The curd was carefully scooped out using a perforated metallic plate, leaving the whey in the churn. The curd was mixed and visually inspected, followed by organoleptic evaluation. Approximately 2.2 litres of raw milk were used to produce about 1 litre of naturally fermented milk. Typical naturally fermented milk produced at the milk center may be described as a "concentrated fermented milk", and this agrees with the classification of fermented fresh milk products given by Kurmann et al (1992). The fermented product is characterised by mild acidity and a slightly lumpy consistency. Naturally fermented was marketed at the centre in consumer-provided containers.
Cultured milk was produced by adding a commercial mesophilic mixed starter culture to heat-treated milk tempered to ambient temperatures. The milk was then allowed to ferment for 16-18 hours, packaged into 500 ml plastic sachets and stored in the cold room at 40C until it was sold. The two fermented milks were consumed with sadza or mixed with other cereal-based local food products. During the warm season, the two types of fermented milks were also drunk despite the rather high viscosity of the naturally fermented product.
Figure 4 also shows that more milk was used for the production of naturally fermented milk. This was most marked during the flush season because there were limited cooling facilities for raw milk and inadequate equipment for the production of larger quantities of cultured milk at the centre. This assertion is supported by the fact that the two types of fermented milks were sold at the same price, although it was apparent that input costs for the cultured milk were higher. The centre therefore resorted to producing more naturally fermented milk as its production is less complicated and requires minimal labour.
The discrepancy between the amount of milk delivered and utilized in a given month is mainly due to losses incurred during the production of naturally fermented milk. Previous studies showed that an average of 55% of milk used for natural fermentation is lost as whey (Mutukumira 1995; McPherson, unpublished). The amount of milk lost by spillages during handling at the milk centre was estimated at 1.5%. No attempt was made to carry out a cost-benefit analysis of the dairy project as this was not part of the objectives of the survey.
The authors are indebted to: Norwegian Universities' Committee for Development Research & Education (NUFU) through the Centre for Development & the Environment, University of Oslo, for financial support; Profesor R K Abrahamsen and Associate Professor J A Narvhus, Dept of Food Science; Agricultural University of Norway, Norway, for their advice during the preparation of this manuscript; Professor F Sundstøl, Dept of Animal Science, Agricultural University of Norway, Norway, for his advice during the preparation of this manuscript; Dr C Mutisi, Dept of Animal Science, University of Zimbabwe, for assistance during the design of the questionnaire.
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(Received 31 December 1995)